Common Summer AC Problems and Solutions

Summer air conditioning problems usually fall into six patterns: rooms that cool unevenly, air that comes out warm, airflow that has faded, ice on the equipment, new noises, and a system that cycles in ways it never used to. Each pattern points toward a different set of causes, and a few of them have safe checks you can run yourself before you pick up the phone.

In the Tri-Cities the equipment works hard. Afternoons in Pasco, Kennewick and Richland stay hot for weeks, the air is dusty, and a system that was fine in June can start showing its weak points by late July.

Some rooms are cool and others are not

Uneven cooling is often an airflow story rather than a refrigerant story. A dirty filter, a closed or blocked register, a crushed flexible duct in the attic, or a duct joint that has come apart can all starve one part of the house. Rooms far from the air handler and rooms over a garage or under a west-facing roof are the first to complain.

Start with the easy part. Check the filter, make sure furniture and rugs are not covering supply vents, and confirm the return grilles are open. If the imbalance stays, the fix may involve duct repair or balancing, and a zoning system is sometimes worth discussing for homes with a big upstairs and downstairs difference.

The air is running but it is not cold

When the blower runs and the air feels lukewarm, the cooling side is not doing its job. Common causes include a dirty outdoor coil that cannot shed heat, a failing capacitor or contactor, a fan motor that has stopped, or a refrigerant leak. Refrigerant is not something that gets used up, so a low charge means there is a leak somewhere, and topping it off without finding the leak only buys a few weeks.

You can check that the thermostat is set to cool with a setpoint below the room temperature, and that the outdoor unit is not buried in cottonwood fluff, grass clippings or dust. Beyond that, refrigerant and electrical parts are work for a licensed technician.

Weak airflow or no air at all

If almost nothing comes out of the vents, look first at the filter. A clogged filter can choke a system down to a whisper. Next, listen at the indoor unit. If you hear no blower at all, a failed blower motor, a bad capacitor, or a tripped breaker may be the cause. Resetting a breaker once is reasonable. If it trips again, stop and call, because something is drawing more current than it should.

Ice on the coil or refrigerant line

Ice is a symptom, not a diagnosis. The usual causes are restricted airflow, often from a dirty filter or a dirty indoor coil, or a low refrigerant charge. If you see frost on the copper line or the indoor unit, turn the cooling off and set the fan to run so the ice can melt. Running the compressor on a frozen coil can damage it.

Once the ice has thawed, replace the filter and try again. If ice returns, the underlying cause is still there and needs a technician.

Strange noises and odd cycling

Different sounds mean different things. Squealing often points to a motor or belt bearing, grinding suggests something has failed mechanically, buzzing can be an electrical part struggling to start, and a rattle may be a loose panel or debris in the fan. A loud bang or a burning smell is a reason to shut the system off at the thermostat and call right away.

Odd cycling deserves attention too. A system that turns on and off every few minutes, runs nonstop without reaching the setpoint, or takes far longer than it used to is telling you something. Oversized equipment, a failing sensor, airflow restrictions and low refrigerant can all cause it.

When to call

• The system trips the breaker more than once
• You see ice that comes back after thawing
• The air stays warm after the filter and thermostat checks
• Any burning smell, loud bang or grinding noise

Air-Tech has been serving Pasco, Kennewick, Richland and the surrounding towns since 2007, and the team works on every brand, not only the ones it sells. Call the office at (509) 392-2021 on weekdays from 8 to 5, or reach the emergency line at any hour when the heat is serious.